A control device of this type is known, for example, from WO 95/28767.
With this circuit, a gate supply voltage of the final stage switch is generated with complicated means.
In addition, DE-A-34 05 936 also discloses a control circuit for an FET final stage switch, in which a diode and a capacitor are present.
However, the capacitor merely serves to charge the gate source capacity of the field effect transistor during switching on. In order to leave this field effect transistor through-connected during the switch-on interval, an additional transistor and a constant current source are required for controlling the transistor and so in this case, as well, the entire gate voltage supply is complicated.